Consider the Nordic skier.
I know, I know, but bear with me.
There’s a lot of chatter about when it becomes “too cold to run.” Some people transition to the treadmill as soon as the first frost hits, while others will dutifully log all their winter miles outside, come snow or freezing temps.
Nordic skiers do not get to head inside as soon as the snow hits. In fact, that’s exactly when they bundle up and head outside. But bundling up is the key – Nordic skiers train outside all winter long because they’re properly prepared to endure the temperatures.
Whether you relish invigorating winter runs or dread the months of bundled-up training, one thing’s for certain: winter running is a different beast than mild-weather running, and you’d best prepare properly.
How Cold is Too Cold to Run?
The biggest question on everyone’s lips is: how cold is too cold to run? Is there a hard and fast line, a degree barrier that you shouldn’t cross?
Unfortunately, it’s not that simple. Depending on size, body fat percentage, and circulation, the cold affects people differently. What may be invigorating for one person might not be tolerable for another.
There are some recommendations that say anything under -20ish Fahrenheit (windchill included) is a good time to stay inside and log some treadmill miles. Some runners tout that there’s no such thing as too cold to run, as long as you’re adequately prepared for the temperature (though I’d be curious to see where their thermometers bottom out).
What Are the Risks of Running in the Cold?
There are two primary dangers to contend with when you’re heading out in the cold: hypothermia and frostbite.
Hypothermia sets in when the body’s core temperature drops below 95 degrees for too long. While you’re running, the major muscle groups will be working and keeping the core warm, meaning that hypothermia is significantly less likely. As soon as you start to decrease your effort, though, the risk increases. You’ll also see increased risk if you’re wet, either from precipitation or perspiration.
In order to avoid those risk factors, it’s important to dress appropriately for the run you have planned and then stick to the plan. If you dress for a hard run and then slow down, you’re probably not insulated enough to keep your temperature up. Similarly, if you dress too warmly, sweat a bunch, and then ease off, you’re lowering your temperature and you’re wet.
Frostbite is, generally speaking, the bigger threat to winter runners. While your core temperature is maintained through exertion, your fingers probably aren’t working as hard (unless you’re running with vigorous jazz hands). The first sign of frostbite is numbness that eventually turns into a tingling and burning sensation – if you experience any of these symptoms, head back in ASAP and contact a medical professional!
Keeping the fingers, toes, and ears warm is paramount and primarily accomplished with protective clothing. Hats, gloves, and robust socks or toe warmers are all valuable tools in the winter runner’s tool kit. In extreme cold, you may need to worry about protecting other exposed skin (as on the face) with a buff, Vaseline, or tape.
Hypothermia and frostbite are the big two, but if you have a chronic (or acute) condition that might be exacerbated by the cold, be smart and self-regulate. The cold can cause an increased risk of heart attack or cardiac event due to the increased stress on your heart. This article is not a replacement for medical advice; call your doctor if you have any questions whatsoever.
Times You Should Absolutely Stay Inside
While the perseverance of runners who brave midwestern winters is admirable, there are a few times when it’s better to just stay inside altogether.
- Arctic temperatures definitely dictate treadmill miles. While it’s true that people have walked to the poles, that’s a completely different game than getting in your weekly workouts. If the temperatures outside are more friendly to polar bears than humans, stay inside.
- Ice provides another potential hazard on top of the cold. If there are icy conditions afoot (ha), stay inside. People slip and fall walking to their cars; attempting a single-legged bounding sport is asking for trouble.
- If it’s wet, take a moment to assess. Running in the rain is usually fine, but running in the rain when there’s snow (or ice) on the ground is dangerous, as is rain combined with wind chill. Remember what we said earlier about being cold and wet? If your feet get wet and cold, you’re more likely to end up with frostbitten toes.
A lot of what it comes down to is (to be blunt), don’t be dumb. If you’re going to be cold and wet, if there’s a high risk of slipping, or if you shouldn’t be outside without a government-grade parka, reconsider your run. Don’t assume you can just power through.
How Does Cold Weather Affect Exercise?
Other than the mental tax of heading out in the cold, there are a few physical impacts you’ll experience as well.
For one, you won’t perform as well as you would during mild conditions. Don’t expect to be hitting PRs or having breakthrough speed workouts. Working out in the cold creates a larger ask for your heart – it has to work harder to pump more blood through your body at a higher rate in order to keep your body warm. Because of this, your muscles won’t be operating at their full capacity and you may have a higher rate of perceived exertion.
The long-term benefits of a higher cardiac workload are there, though. Because your heart is working harder to get blood to your extremities, you’re training the efficiency of your heart – and it shows when you get back to normal, human-approved temperatures. In a study of cyclists who trained in both hot and cold conditions, upon returning to mild conditions, the cold-weather trainees demonstrated a 5% increase in power output at lactate threshold.
Beyond the added cardiac ask, your warm up becomes even more important in frigid temperatures. Not only is the body working harder to stay warm, but your muscles and tendons are less pliable and will negatively impact your running form. If you head out without a proper warm up, you’re not going to bend into your knees and hip as much as normal, resulting in greater loading forces and increasing your risk for injury. Your tendons are also stiffer; warming up increases the blood flow to key areas and reduces the risk of overuse or acute injuries.
On the plus side, once you’re done with the run, there’s a positive perk: many athletes who workout in “uncomfortable” conditions report feeling like they’ve accomplished more. Because of the mental effort it takes to overcome adversity, the sense of accomplishment is proportionately great.
Tips for Running in the Cold
So, with all the added stress of the cold weather, how can you ensure a successful winter running season? Luckily, aside from the mental toughness, running in the cold only requires a few deliberate shifts in preparation.
Activity Adaptations
Planning your runs appropriately can both set you up for success and help to keep you safe and injury-free. Make sure that before you head out, you have a plan in place for both your workout and your bailout.
First and foremost, don’t head out planning to do speedwork or looking to push the pace. Winter runs, especially frigid or snowy ones, are more about maintenance and base building. Leave the hard workouts for more amenable climes. Similarly, if you’re out and something doesn’t feel right, go home. You can always switch to a treadmill or go back out tomorrow.
When you’re planning your route, stay somewhere familiar. The worst thing you can do is frozen temperatures is get lost. Shorter laps that you can run multiple times are your friend. You don’t have to go run 5 miles on a track, but look for a loop in your neighborhood or in a familiar area that takes you past your starting point multiple times. This way, if you need to adjust on the fly, you don’t find yourself halfway through an out-and-back with no way to cut the run short.
As mentioned in the previous section, the warm up becomes an even more important part of your workout. Keep your muscles and tendons safer with a longer warm up. Move around inside before heading out doors.
Don’t lollygag when you’re cooling down, either. The sweat you work up during your run places you at higher risk for hypothermia if you remain outside while your clothes are wet. Aim to finish your route near your car or your home so that you can be in heated temperatures shortly after your run concludes.
Clothing Adaptations
Perhaps more than anything, your attire is important in getting through the run. When you’re looking at the outdoor temperature, play attention to wind chill or what the “feels like” temperature is. This is a far better indicator of conditions than a straight degree. Also, be aware of humidity. Wet cold feels MUCH colder than dry cold.
There are myriad options for articles that denote clothing based on the temperature. Find one and bookmark it until you get a feel for what works for you at different temperatures.
As temperatures drop, make sure your ears and extremities are protected. Gloves and a hat or a headband should be the first staples in your winter running wardrobe. If you’re on the edge about wearing a hat or gloves, err on the side of wearing them. You’d much rather take the hat off then end of with frozen ears.
In extreme conditions, a buff to cover your mouth and nose can make a huge difference. If it’s cold enough to potentially damage your skin, Vaseline can form a protective barrier and keep moisture in. Some runners will go as far as to tape the outside of their shoes with duct tape to keep cold air from penetrating through the fabric or mesh.
Fuel Adaptations
Water and food need don’t require too much change, but they do merit conscious attention.
Because staying warm in the cold requires more energy, you’ll need to up your calorie intake slightly. Eat a little more before you head out, and take a gel (or preferred running snack) with you. Far better to have it and not need it than miss it part way through your run. Being overly fatigued during your run becomes much more dangerous when you’re dealing with the possibility of hypothermia.
Water might require a little more discipline. When it’s cold, especially if you’re outside, you’re less likely to drink water. Your body still has the same hydration needs, though. Be deliberate about drinking water before you head out, and have a plan for during your run.
In the cold air, you might actually find that your water bottle freezes, or the water becomes too cold to comfortably drink. If you’re looping by your house, you can stop in and get room temperature, distinctly-not-frozen water. If heading inside partway through your run doesn’t sound like your cup of tea (or just isn’t an option), plan to insulate your water bottle to keep it from freezing. Some runners have reported that putting a hand warmer next to the bottle not only keeps it liquid, but much more palatable.
All Things Considered
Altogether, running in through winter months is totally doable, even if you live in an area prone to the winter wonderland aesthetic. Make the appropriate adjustments to your training plan and remember that winter months aren’t for serious performance gains – you’re just looking to create a base that all your spring training will build on.
Happy training! Stay warm!
